睡眠が脳の健康について大変重要だ！なんて誰でも想像できるお話だけど、一応科学的に解説できるよというお話を見つけた。
2019年11月8日のサイエンスニュースから。
Sleep may trigger rhythmic power washing in the brainというタイトル。
概要は、睡眠中に脳内で強弱の波をおこし、その波によって脳内にある有害なタンパク質を排泄しているということ。
原文はこちら
Every 20 seconds, a wave of fresh cerebrospinal fluid rolls into the sleeping brain. These slow, rhythmic blasts, described for the first time in the Nov. 1 Science, may help explain why sleep is so important for brain health.
Studies on animals have shown that the fluid, called CSF, can wash harmful proteins, including those implicated in Alzheimer’s disease, out of the brain. The new results give heft to the idea that a similar power wash happens in sleeping people.
Researchers studied 13 healthy, young people in an MRI scanner as they fell into non-REM sleep, the type of slumber that takes up most of the night. At the same time, the scientists monitored different sorts of activity in participants’ heads. Electrodes measured the activity of large collections of nerve cells, and functional MRI measured the presence of oxygenated blood that gives energy to those nerve cells. By using a form of rapid fMRI, the team also measured another type of activity — the movements of CSF in the brain.
Fast fMRI revealed waves of fresh CSF that flowed rhythmically into the sleeping brains, a pattern that was obvious — and big, says study coauthor Laura Lewis, a neuroscientist and engineer at Boston University. “I’ve never had something jump out at me to this degree,” she says. “It was very striking.”
この有害なタンパク質は脳の健康もだけど、アルツハイマー病の原因にもなると考えられてるそうです。
これ、すごく秀逸なイラストだと思う。
